What is the difference between central vertigo and BPPV (Benign Paroxysmal Peripheral Vertigo)?

Central Vertigo vs BPPV: Key Differences and Diagnostic Features

Central vertigo and BPPV (Benign Paroxysmal Positional Vertigo) can be differentiated primarily by nystagmus characteristics, associated neurological symptoms, and response to positional testing, with central vertigo carrying significantly higher morbidity and mortality risks.

Pathophysiology

• BPPV: Caused by otoconia (calcium carbonate crystals) that have detached from the otolithic membrane and float freely within the endolymph of the semicircular canals (canalolithiasis) or adhere to the cupula (cupulolithiasis) 1
• Central vertigo: Results from lesions in the central nervous system, particularly in the cerebellum, brainstem, or vestibular nuclei 2

Nystagmus Characteristics

BPPV Nystagmus:

• Has a torsional component
• Fatigues with repeated testing
• Can be suppressed by visual fixation
• Direction is specific to the affected canal:
  • Posterior canal: Upbeating torsional nystagmus
  • Lateral canal: Horizontal geotropic or apogeotropic nystagmus
  • Anterior canal: Downbeating with torsional component 3, 4

Central Vertigo Nystagmus:

• Pure downbeating nystagmus without torsional component
• Direction-changing nystagmus without changes in head position
• Baseline nystagmus without provocative maneuvers
• Does not fatigue with repeated testing
• Cannot be suppressed by visual fixation 3, 4

Clinical Presentation

BPPV:

• Brief episodes of vertigo (typically <1 minute)
• Triggered by specific head movements relative to gravity
• Symptoms fatigue with repeated positioning
• No associated neurological symptoms
• Responds to canalith repositioning procedures (70-90% success rate) 3, 1

Central Vertigo:

• May have longer duration of vertigo
• Often accompanied by additional neurological findings:
  • Dysarthria
  • Dysmetria
  • Dysphagia
  • Sensory or motor deficits
  • Cranial nerve abnormalities
• Does not respond to repositioning maneuvers
• May present with severe postural instability 4, 2

Red Flags for Central Pathology

• Downbeating nystagmus without torsional component
• Direction-changing nystagmus without head position changes
• Persistent nystagmus without fatigue
• Associated neurological symptoms
• Failure to respond to appropriate repositioning maneuvers
• Severe postural instability 3, 4, 5

Diagnostic Approach

For BPPV:

1. Dix-Hallpike test for posterior canal BPPV

   • Positive: Delayed onset (1-5 seconds), torsional upbeating nystagmus
   • Symptoms and nystagmus fatigue with repeated testing

2. Supine roll test for horizontal canal BPPV

   • Geotropic: Nystagmus beats toward the ground in both positions
   • Apogeotropic: Nystagmus beats away from the ground in both positions 3, 1

For Central Vertigo:

1. Look for:

   • Pure vertical nystagmus
   • Direction-changing nystagmus without head position change
   • Nystagmus that doesn't fatigue
   • Associated neurological findings

2. Consider neuroimaging if:

   • Atypical nystagmus patterns
   • Neurological symptoms present
   • Failed response to appropriate repositioning maneuvers 4, 2, 5

Important Clinical Considerations

1. Cerebellar stroke can mimic peripheral vertigo in approximately 10% of cases, presenting with isolated vertigo similar to peripheral vestibular disorders 4

2. Isolated transient vertigo may precede vertebrobasilar stroke by weeks or months, requiring careful evaluation 3, 4

3. Central positional vertigo may be the sole presenting feature of serious neurological conditions such as posterior fossa tumors 5

4. Patients with suspected horizontal or anterior canal BPPV with atypical features should be examined by a neurologist to rule out central causes 6

Treatment Response as Diagnostic Tool

• BPPV: Responds well to specific canalith repositioning procedures

  • Posterior canal: Epley maneuver
  • Lateral canal: Gufoni maneuver or barbecue roll

• Central vertigo: Fails to respond to repositioning maneuvers 3, 4

Conclusion

When evaluating patients with positional vertigo, careful attention to nystagmus characteristics, associated symptoms, and response to positioning tests is crucial for differentiating between BPPV and central vertigo. Any features inconsistent with typical BPPV should raise suspicion for central pathology and warrant further investigation to prevent delays in diagnosing potentially serious neurological conditions.